update route crd destinations when deleting route mappings

* should delete them on cascading deletes as well

[finishes #171827218]
https://www.pivotaltracker.com/n/projects/2407973/stories/171827218

Authored-by: Connor Braa <cbraa@pivotal.io>

Co-authored-by: Connor Braa <cbraa@pivotal.io>
Co-authored-by: Seth Boyles <sboyles@pivotal.io>

Author: cwlbraa

app/actions/route_mapping_delete.rb

@@ -29,12 +29,20 @@ def delete(route_mappings)
           route_handlers.each do |handler|
             handler.update_route_information(perform_validation: false)
           end
+
+          if VCAP::CloudController::Config.kubernetes_api_configured?
+            route_crd_client.update_destinations(route_mapping.route.reload)
+          end
         end
       end
     end
 
     private
 
+    def route_crd_client
+      CloudController::DependencyLocator.instance.route_crd_client
+    end
+
     def event_repository
       Repositories::AppEventRepository.new
     end

app/actions/update_route_destinations.rb

@@ -98,8 +98,7 @@ def update(route, to_add, to_delete, user_audit_info, manifest_triggered)
         route.reload
 
         if VCAP::CloudController::Config.kubernetes_api_configured?
-          client = route_crd_client
-          client.update_destinations(route)
+          route_crd_client.update_destinations(route)
         end
 
         route

spec/unit/actions/app_delete_spec.rb

@@ -11,9 +11,11 @@ module VCAP::CloudController
     let!(:app) { AppModel.make }
     let!(:app_dataset) { [app] }
     let(:kpack_client) { instance_double(Kubernetes::KpackClient, delete_image: nil) }
+    let(:route_crd_client) { instance_double(Kubernetes::RouteCrdClient, update_destinations: nil) }
 
     before do
       allow(CloudController::DependencyLocator.instance).to receive(:kpack_client).and_return(kpack_client)
+      allow(CloudController::DependencyLocator.instance).to receive(:route_crd_client).and_return(route_crd_client)
     end
 
     describe '#delete' do

spec/unit/actions/route_mapping_delete_spec.rb

@@ -22,6 +22,10 @@ module VCAP::CloudController
       allow(ProcessRouteHandler).to receive(:new).with(process2).and_return(process2_route_handler)
       allow(Repositories::AppEventRepository).to receive(:new).and_return(event_repository)
       allow(event_repository).to receive(:record_unmap_route)
+      TestConfig.override(
+        kubernetes: {
+        },
+      )
     end
 
     describe '#delete' do
@@ -50,6 +54,26 @@ module VCAP::CloudController
           expect(process2_route_handler).to have_received(:update_route_information).with(perform_validation: false)
         end
 
+        describe 'when k8s is configured' do
+          let(:route_crd_client) { instance_double(Kubernetes::RouteCrdClient) }
+          before do
+            TestConfig.override(
+              kubernetes: {
+                host_url: 'some-kubernetes-host-url'
+              },
+            )
+            allow(CloudController::DependencyLocator.instance).to receive(:route_crd_client).and_return(route_crd_client)
+            allow(route_crd_client).to receive(:update_destinations)
+          end
+
+          it 'removes the destination from the mapped route' do
+            expect(route_mapping).to receive(:destroy).ordered
+            expect(route_crd_client).to receive(:update_destinations).with(route).ordered
+
+            route_mapping_delete.delete(route_mapping)
+          end
+        end
+
         describe 'audit events' do
           it 'records an event for un mapping a route to an app' do
             route_mapping_delete.delete(route_mapping)